A national PBS documentary will point to Portland as one of three cities that exemplify how the nation can use transportation infrastructure to fight sprawl, preserve the environment and promote mass transit.

It uses Denver, New York and Portland - and their nearby suburbs - as examples of how national policies on transportation can shape cities.

Producers hope the show and related segments other PBS programs will influence upcoming debates on a new multi-year federal transportation bill and stimulus spending.

"How we build ultimately will determine how we live and the quality of life we enjoy," said Neal Shapiro, chief executive officer of WNET.ORG. "For many years, cities have been neglected, and in many cases harmed, by government policies that favored sprawl over density."

But reporter Miles O'Brien also features landowners frustrated by Portland-area growth restrictions and a Denver-area family that seems content with a suburban lifestyle. And he explains the continued popularity of car-friendly policies, citing as an example the defeat of New York Mayor Michael Bloomberg's proposal to charge tolls on cars entering the city to boost mass transit funding.